leetcode701

 class Solution:

     def insertIntoBST(self, root, val):
         """
         Time:  O(log(n))  [average case]
         Space: O(1)
         """
         new_node = TreeNode(val)

         if not root:
              return new_node

         curr = root
         while True:
             if curr.val > val:
                 if not curr.left:
                     curr.left = new_node
                     break
                 else:
                     curr = curr.left
             else:
                 if not curr.right:
                     curr.right = new_node
                     break
                 else:
                     curr = curr.right
         return root